1. Field of The Invention
Applicant's invention relates to multi-purpose medical dressings, in particular, dressings for treating open chest injuries or other injuries that compromise, or could possible compromise the pleural space of the chest cavity. Specifically, a medical dressing used by first responders to treat an open pneumothorax, treat or prevent a tension pneumothorax from developing without invasive procedures, evacuate the pooled blood in a hemothorax or re-inflate a collapsed lung without invasive procedures, and, in some instances, act as a conduit for treating a collapsed lung or a tension pneumothorax with invasive procedures.
2. Background Information
FIG. 6 is a diagram of the chest cavity. When a person is shot or stabbed in the chest, the wound often times penetrates a sufficient distance into the chest cavity to puncture the parietal pleura, visceral pleura, and the lungs. In some cases two wound holes are formed, an entry and an exit hole. A wound hole(s) that penetrates the chest cavity and parietal pleura allows air and/or blood to flow freely into the chest cavity, the pleural space, and possibly the lungs.
The condition wherein air penetrates into the pleural space between the lung and the chest wall through a wound hole in the chest wall is an open pneumothorax. When an open pneumothorax occurs, the normal mechanism by which the lung expands is lost; i.e., the fluid adhesion of the pleural surface of the lung to the pleural surface of the chest wall. Thus, the affected lung does not expand when the patient inhales and respiratory distress becomes severe and possibly fatal. For patients with an open wound to the chest, the severity of the open pneumothorax that develops can be minimized by sealing the open wound via an occlusive bandage prior to transport. The occlusive bandage is used to eliminate air penetrating into the pleural space through the wound hole when the patient inhales. If the intake of air into the pleural space is not entirely eliminated, additional air will be trapped in the pleural space, thus causing the pressure in the affected chest cavity to rise. If the pressure in the chest cavity exceeds normal pressure, blood flow from the heart to the lungs may be halted, with death rapidly following. Thus, it is imperative that when treating an open pneumothorax, that the wound is appropriately sealed in a manner which eliminates air from penetrating into the pleural space through the wound hole.
The current day medical procedures used by first responders to treat an open pneumothorax are occlusive type dressings. For example, (1) petrolatum gauze dressing, (2) a sterilized aluminum foil dressing, or (3) a folded universal dressing placed over the wound. The gauze dressing, foil or universal dressing is taped to the skin on all four sides of the wound. By taping the dressing on all four sides, the first responder is attempting to eliminate air penetrating into the pleural space through the wound. Yet, in most instances, this type of dressing is ineffective. It either (1) does not totally eliminate air entering the pleural space through the wound; (2) eliminates air penetrating into the pleural space through the wound yet does not allow the already trapped air to escape; or (3) a combination of both. These defects could cause a more serious tension pneumothorax to develop which leads to respiratory insufficiency and heart failure. Consequently, a need exists for a method and apparatus for successfully treating an open pneumothorax that can be used by first responders, which totally eliminates the intake of outside air into the pleural space via the wound hole yet allows already trapped air to escape.
In addition to developing a tension pneumothorax by using defective dressings as discussed above, a patient with an open chest wound and a severe lung laceration may also develop a tension pneumothorax in a different manner. For instance, the bandage may have eliminated air from entering the pleural space through the wound hole, yet if lacerated, the lung will continue to leak air into the pleural space. Consequently, every time the patient inhales, more air becomes trapped in the pleural space, causing more pressure to be exerted on the lacerated lung. This increased pressure on the lacerated lung forces the lung to collapse until reduced to a ball 2-3 inches in diameter. At this point of collapse, pressure in the affected chest cavity begins to rise, the collapsed lung is pressed against the heart and the lung on the opposite side, compressing the remaining uninjured lung. If the pressure in the chest cavity exceeds the normal pressure of the blood returning to the heart, blood flow from the heart to the lungs may be halted, with death rapidly following.
To successfully prevent a tension pneumothorax from developing, the air flow into the pleural space via the wound hole must be eliminated, but the air coming from the lacerated lung must be allowed to escape the pleural space via the wound hole. The method of treatment currently used by first responders is the same type of dressing used to treat an open pneumothorax except it is taped on only three sides of the wound. The untaped side of the bandage theoretically allows air to exit the pleural space through the wound hole when the patient exhales. As the patient inhales, the three sided dressing theoretically collapses against the wound, thus prohibiting air from entering the pleural space through the wound hole.
In most instances, three sided dressings are ineffective. Initially, the amount of blood that normally accompanies the chest wound prohibits the tape from securely attaching the dressing to the patient. Secondly, when the petrolatum gauze dressing is opened, it becomes creased, making it less form fitting to the body. Consequently, air can both enter and exit the chest cavity because the petrolatum gauze is not sucked against the wound when the patient inhales. Petrolatum is also necrotizing to the lung tissue. If petrolatum penetrates the wound and contacts the lung tissue, the lung tissue may die. Finally, for less experienced or less trained first responders, their common protocol when treating any type of chest wound is to apply a totally occlusive, four-sided bandage instead of a non-occlusive three-sided dressing. If a four-sided bandage is used in conjunction with a lacerated lung, or an already developing tension pneumothorax, the results can be deadly. Consequently a need exists for a medical dressing for use by first responders that effectively treats both an open pneumothorax and a tension pneumothorax and accordingly does not require the first responder to determine if a three sided or four sided bandage is required.
Other than the above described ineffective three sided or four sided dressings, the only other procedure currently used to treat or prevent a tension pneumothorax from developing is an invasive procedure using a needle thoracentesis (FIG. 1O) that may only be performed by highly trained medical professionals. Therefore, a need exists for a method and apparatus for treating or successfully preventing a tension pneumothorax from developing which does not require invasive procedures. The apparatus must allow air to escape from the pleural space, yet not allow air to enter the pleural space through the wound hole.
In some instances, medical personnel having the training to perform a needle thoracentesis are on the scene. A needle thoracentesis is an invasive procedure to immediately decompress a tension pneumothorax. It is performed when a tension pneumothorax has progressed to a point that the affected lung has completely collapsed, putting pressure on the mediastinum, which affects the operation of the heart and the good lung.
The needle thoracentesis procedure consists of taking a large bore catheter, 14 gauge or larger, and inserting it into the second intercostal space in the mid-clavicular line of the patient's chest on the side of the tension pneumothorax. The catheter is inserted until trapped air begins to escape from the plural space. The catheter remains in the chest to allow all pressure to escape. After air stops escaping through the catheter, it is also removed. After the catheter is removed, if a tension pneumothorax begins to again develop, it becomes necessary to repeat the above procedure which is very time consuming and cost ineffective. Furthermore, on the battle field, medics do not have the time to continually repeat the needle thoracentesis on several patients. Consequently, a need exists that would allow a mechanism for the catheter to be maintained in the chest yet, securing the catheter in such a manner that it does not become inoperable and possibly forced into a position harmful to the patient.
In addition to a tension pneumothorax, a patient with a chest wound may also experience a hemothorax. A hemothorax is the presence of blood in the pleural space. The blood in the pleural space may come from lacerated vessels in the chest wall, from lacerated major vessels within the chest cavity itself, or from a lacerated lung. In a hemothorax, the pleural space becomes filled with blood. Normal lung expansion does not occur, and the lung itself is compressed, thus less air is inhaled. In addition, significantly less blood may be available to carry the reduced level of oxygen to the patient's vital organs.
To treat a hemothorax, the blood must be removed from the pleural space to allow the lung to expand to its normal capacity. Current day treatment of a hemothorax by a first responder includes application of an occlusive dressing over the wound, positioning the patient onto the injured side, thus limiting the pooled blood to the wound side of the chest cavity, immediate ventilatory support, administration of oxygen, and immediate transportation to the hospital. Treatment by first responders does not currently include removal of the accumulated blood from the pleural space.
Removal of the blood in the pleural space does not occur until the patient is in the hospital. Once in the hospital, a chest tube is inserted into the wound and negative pressure, i.e. suction, is applied to remove the accumulated blood in the pleural space. If a sufficient quantity of blood accumulates in the pleural space before the patient arrives at the hospital, the lacerated lung may collapse. Therefore, it is imperative that the blood be removed from the pleural space as soon as possible. Consequently, a need exists for a method and apparatus to be used by a first responder for removal of blood in the chest cavity.
An unwanted result of a tension pneumothorax and a hemothorax is a collapsed lung. Currently, a collapsed lung is only re-inflated through invasive procedures in the hospital. First responders at this time do not treat a collapsed lung. If a collapsed lung is not treated, it can lead to further respiratory difficulties in an already traumatized patient. Consequently, a need exists for a method and apparatus for successfully re-inflating a collapsed lung by a first responder.
Finally, medics on the battlefield face dilemmas everyday due to the limited space in a medic's pack. Consequently, when the bandage used to treat often encountered wounds on a battlefield is compact, the compactness increases each wounded soldier's chances of survival. Chest wounds are one of the most encountered injuries on a battlefield. Consequently, a need exists for a small, compact yet efficient bandage that can be used on the battlefield to treat open chest wounds. In addition to being compact, the bandages must require little attention after application, and continue to operate for at least an hour after application due to distances from the battlefield to the nearest care facility.